The present invention relates to a spot welding electrode housing apparatus where an electrode for spot welding to be used in, for example, automobile manufacturing lines is housed so as to be mountable to a shank of a welding gun.
In conventional automobile manufacturing lines, a plurality of press molded products are joined by spot welding to assemble a vehicle frame, and the spot welding is generally performed using a welding gun attached to a front edge of an arm of an industrial robot.
An electrode is mounted to the shank of the welding gun by fitting the distal end of the shank in a fitting recess of the electrode. The electrode is worn out through repetition of spot welding, and thus, needs to be periodically exchanged with another one. Thus, in exchanging electrodes, to efficiently mount an electrode to the shank of the welding gun, a spot welding electrode housing apparatus is placed on automobile manufacturing lines.
For example, an electrode housing apparatus disclosed in Japanese Unexamined Patent Application Publication (Translation of PCT Application) No. 2013-514182 includes a square tubular housing case including a housing path therein, and the housing path can house electrodes in a state where the electrodes are arranged linearly in a direction orthogonal to the center axes of the electrodes and fitting recesses are arranged in parallel and are open in the same direction. An end of the housing case has an electrode outlet port communicating with the housing path, whereas the inside at the other end of the housing case is provided with a pressing unit that presses one or a plurality of parallel electrodes housed in the housing path against one end of the housing path by a spring force. On an end of the housing case, an ejection regulating member that is movable in a direction orthogonal to the longitudinal direction of the housing case is disposed. The ejection regulating member covers a part of the electrode outlet port when moved to one end by a biasing force of a coil spring to regulate ejection of an electrode from the electrode outlet port, and enables ejection of an electrode from the electrode outlet port when moved to the other side against a biasing force of the coil spring. When the shank distal end is fitted in a fitting recess of an electrode contacting the ejection regulating member in the electrodes disposed in parallel in the housing path and the shank distal end is moved to an end of the housing path, an electrode is ejected from the electrode outlet port that is exposed by movement of the ejection regulating member to the other side against the biasing force of the coil spring. Thereafter, an electrode adjacent to the ejected electrode moves to an end of the housing path by the spring force of the pressing unit, and contacts the ejection regulating member that has moved to one side by the biasing force of the coil spring so that ejection from the electrode outlet port is regulated.